History is taken and broken down into a series of Aeons, each with its own dominant concept of divinity and its own "formula" of redemption and advancement. According to Aleister Crowley, the last three Aeons have been (1) the Aeon of Isis, (2) the Aeon of Osiris, and (3) the current Aeon of Horus which began in 1904.

The three Aeons

The first Aeon of Isis was maternal, where the female aspect of the Godhead was revered due to a mostly matriarchal society and the idea that "Mother Earth" nourished, clothed and housed man. It was characterized by pagan worship of the Mother and Nature. Crowley describes this period as "simple, quiet, easy, and pleasant; the material ignores the spiritual" (Equinox of the Gods).

The Classical/Medieval Aeon of Osiris is considered to be dominated by the Paternal Principle and the formula of the Dying God. This Aeon was characterized by that of self-sacrifice and submission to the Father God. Crowley says of this Aeon:

Formula of Osiris, whose word is IAO; so that men worshiped Man, thinking him subject to Death, and his victory dependent upon Resurrection. Even so conceived they of the Sun as slain and reborn with every day, and every year. (Heart of the Master)

He also says of the Aeon of Osiris in Equinox of the Gods:

the second [Aeon] is of suffering and death: the spiritual strives to ignore the material. Christianity and all cognate religions worship death, glorify suffering, deify corpses.

The modern Aeon of Horus, with our times of self-realization as well as a growing interest in all things spiritual, is considered to be dominated by the Principle of the Child. The Word of its Law is Thelema (will) which is complimented by Agape (love), and its formula is Abrahadabra. Individuality and finding the "True Will" are the dominant aspects; its formula is that of growth, in consciousness and love, toward self-realization.

Of the Aeon of Horus, Crowley writes:

the crowned and conquering child, who dieth not, nor is reborn, but goeth radiant ever upon His Way. Even so goeth the Sun: for as it is now known that night is but the shadow of the Earth, so Death is but the shadow of the Body, that veileth his Light from its bearer. (Heart of the Master)

And also:

The Aeon of Horus is here: and its first flower may well be this: that, freed of the obsession of the doom of the Ego in Death, and of the limitation of the Mind by Reason, the best men again set out with eager eyes upon the Path of the Wise, the mountain track of the goat, and then the untrodden Ridge, that leads to the ice-gleaming pinnacles of Mastery! (Little Essays Towards Truth, "Mastery")

Other aeons

The future Aeon, which is seen to eventually replace the present one, is the Aeon of Ma'at. According to some—such as Charles Standfield Jones (Frater Achad)—the Aeon of Maat has already arrived. For others, (among them Nema, and the Horus Maat lodge) it is present as a backwards-flowing current grounded in the future.

Temporal aspects

There is a debate as to the temporal span of an Aeon. On the one hand it is argued that an Aeon lasts 2000 years in accordance with the astrological ages generated by the procession cycles of the earth's axis (ie; the 26000 year 'platonic year'), while on the other, Crowley himself suggested that the Horus Age may last as little as 100 years, and that the Aeons might not be uniformly defined in terms of duration. Still another point of view suggests that an Aeon is better interpreted in light of the Gnostic model in which Aeons (or Aions) are considered as stages or spheres of influence in terms of the development of an energy. As such, in this view an Aeon is not Chronological at all, and it is possible for several Aeons to co-exist on the Earth at one time. Contemporary earthly existence of 'prehistoric' cultures, patriarchal structures, and Horus-influenced bastions of individualism, are cited as support for this hypothesis of heterogeneous Aeonics.